GED Science Practice Questions

If you've heard rumors about the GED being changed and are worried that these questions no longer apply, there's no need for concern. The new improved GED doesn't start until 2014. Until then, these samples are great practice.

1. The pilot of an eastbound plane determines wind speed relative to his aircraft. He measures a wind velocity of 320 km/h, with the wind coming from the east. An observer on the ground sees the plane pass overhead, and measures its velocity as 290 km/h. What is the wind velocity relative to the observer?

2. A recycling company collects sorted materials from its clients. The materials are weighed and then processed for re-use. The chart shows the weights of various classes of materials that were collected by the company during a representative month. Which of the following statements is NOT supported by the data in the chart?

1. Paper products, including cardboard, make up a majority of the collected materials
2. One quarter of the materials collected are made of glass
3. More plastic is collected than cardboard
4. Plastic and cardboard together represent a larger portion of the collected materials than glass bottles
5. The largest category of collected materials includes newspapers

3. During the process of oogenesis, primary oocytes produce:

1. Sperm
2. Eggs
3. Oogonia
4. Stem cells
5. None of the above

Questions 4-6 are based upon the following figure and text:

4. Electrons are produced by a chemical reaction that takes place at the:

6. In a car battery, a product of the oxidation reaction that occurs at the cathode is:

1. Lead oxide
2. Lead
3. Electrons
4. Water
5. Sulfuric acid

Questions 7-8 are based upon the following figure:

7. Colonies of silkworms containing the same number of genetically identical or genetically varying animals were established. For several weeks after the colonies were created, silk production was estimated by removing small samples of silk from the colonies and weighing them. The results are shown in the graph. The open symbols refer to the production of silk by genetically uniform worms, while the closed symbols refer to production of silk by genetically diverse worms. Which of the following conclusions can be drawn from the data?

1. In the mouth
2. In the stomach
3. In the pylorus
4. In the duodenum
5. In the ileum

Questions 10-13 are based upon the following figure and text:

Energy from the sun heats the water in the oceans and causes it to evaporate, forming water vapor that rises through the atmosphere. Cooler temperatures at high altitudes cause this vapor to condense and form clouds. Water droplets in the clouds condense and grow, eventually falling to the ground as precipitation. This continuous movement of water above and below ground is called the hydrologic cycle, or water cycle, and it is essential for life on our planet. All the Earth's stores of water, including that found in clouds, oceans, underground, etc., are known as the hydrosphere.

Water can be stored in several locations as part of the water cycle. The largest reservoirs are the oceans, which hold about 95% of the world's water, more than 300,000,000 cubic miles. Water is also stored in polar ice caps, mountain snowcaps, lakes and streams, plants, and below ground in aquifers. Each of these reservoirs has a characteristic residence time, which is the average amount of time a water molecule will spend there before moving on. Some typical residence times are shown in the table.

The water cycle can change over time. During cold climatic periods, more water is stored as ice and snow, and the rate of evaporation is lower. This affects the level of the Earth's oceans. During the last ice age, for instance, oceans were 400 feet lower than today. Human activities that affect the water cycle include agriculture, dam construction, deforestation, and industrial activities.

12. Other than atmospheric water, water molecules spend the least time in:

1. Aquifers
2. Oceans
3. Glaciers
4. Ice caps
5. Soil

13. Which of the following statements is NOT true?

1. Cutting down trees affects the water cycle.
2. Ocean levels rise during an ice age.
3. Oceans hold most of the world's water.
4. Clouds are formed because of cold temperatures.
5. Rain and snow are forms of precipitation.

Questions 14-15 are based upon the following figure and text:

When the molecules of a substance absorb energy in the form of heat, they begin to move more rapidly. This increase in kinetic energy may be a more rapid vibration of molecules held in place in a solid, or it may be motion through molecular space in a liquid or a gas. Either way, it will be observed as either a change in temperature or a change in state. Heat has traditionally been measured in terms of calories. One calorie is equal to 4.186 Joules.
The specific heat capacity of a substance is the energy required to raise the temperature of 1 kg of the substance by 1°C. For water, this is 1000 calories. If heat continues to be applied to ice that is already at its melting point of 0°C, it remains at that temperature and melts into liquid water. The amount of energy required to produce this change in state is called the heat of fusion, and for water it is equal to 80 calories per gram. Similarly, the amount of energy required to change a gram of liquid water at 100°C into steam is called the heat of vaporization, and equals 540 calories.
The graph shows an experiment in calorimetry: 1 gram of water at -50°C is heated slowly from a solid state until it has all turned to gas. The temperature is monitored and reported as a function of the heat added to the system.

1. Adding heat to a system always increases its temperature.
2. The average speed of a gas molecule is slower than the average speed of a liquid molecule of the same substance.
3. Adding heat to a system always increases the average speed of the molecules of which it is comprised.
4. Heat must be added to liquid water to make ice.
5. It takes more energy to melt a gram of water at 0°C than it does to turn a gram of water at 100°C into steam.